1. Field of the Invention
The invention includes sink basin countertop fabrication. More specifically, the invention includes a method and apparatus to position and mount a sink basin on the underside of a pre-manufactured, solid polymer or polymer-veneered countertop.
2. Background Information
A sink may be thought of as a water basin fixed to a wall or floor, surrounded by a countertop as a level surface, and serviced by both a piped supply of water and a drainpipe. Sink basins mounted from the underneath side of a countertop may be installed in polymer countertops by one of two methods: (i) either by chemical fusion using an epoxy-type adhesive so that the sink basin becomes integral with the countertop; or (it mechanically securing the sink basin to the countertop using mechanical fasteners and sealant. Both of these methods of installation are normally performed in specialized fabrication shops through a highly skilled process.
The highly skilled installation process may involve the following steps: (1) penciling square reference lines at the desired sink basin location on the top surface of a countertop; (2) positioning the sink basin on the countertop and tracing the sink basin perimeter precisely over the reference lines; (3) removing the sink basin and cutting an opening in the countertop as defined by the tracing; (4) turning the countertop over (an operation which often requires two workers); (5) drawing new square reference lines; (6) positioning the sink basin carefully over the cut opening; (7) preparing and attaching a number of sink basin positioning blocks around the sink opening perimeter; (8) removing the penciled lines by solvent or sanding, so as not to blemish the fused sink seam or sealant; (9) applying adhesive or sealant to the sink basin flange; (10) again setting the sink basin carefully in place; and (11) attaching mechanical fasteners such as clamps to secure the sink basin to the countertop.
The above process may take a half-hour longer for a skilled fabricator to install even a small sink basin. Solid polymer basins that are integrally mounted into a countertop made of a particle board substrate with a veneered polymer overlay may require the additional step of routing away the substrate material below the veneer surface to provide a polymer-to-polymer joint. This step is very precise and requires a fabricator of the highest skill level. This is one reason why the use of integrally mounted polymer sinks in veneered polymer counters is limited in the conventional art. In addition to these problems, there are many opportunities for error in every step of the current methodology of under mounting sink basins. Mitigating these potential for errors requires the employment of only skilled, expensive journeypersons in these tasks.
In more advanced fabrication shops, plywood outline templates are often used to locate and trace the sink basin perimeter to be cut, eliminating the need to draw square reference lines. In some instances, plywood router templates are used in cutting the opening over which the sink basin is then mounted. Although the use of these templates reduces errors and process time somewhat, the overall task still requires a highly skilled worker and a good deal of time. For instance, although a router template to cut a sink opening may facilitate a smooth and properly shaped opening, the router template will not obviate the need for tracing the sink basin, for fabricating and attaching sink basin positioning blocks, and for removing the tracing lines.
One of the more time consuming elements of the current methodology involves the process of clamping integrally mounted basins to a countertop work piece. After having reached that stage in the overall process outlined above at which the sink basin is ready to be mounted, a plywood clamping template is positioned below the countertop by a worker such that the plywood overlaps the sink basin opening. The worker below then passes an adjustable clamping device through a prepared hole in the plywood template, then through the sink basin opening, and also through the sink basin drain hole, whereby the sink basin is clamped firmly to the countertop by a second worker positioned above the countertop. This operation often requires two workers to both clamp and remove the plywood template. Also, this method of mounting basins requires a special topless workbench that permits access below to apply and remove the plywood template and clamping device. Since this workbench is not always the best work surface for other types of operations, additional time and material expense are required to change bench configurations for different shop functions.
Collectively, these conventional methods represent the fabrication industry's "best practice", as recommended by the various sink basin manufacturers, yet they do not meet the need for a fast, efficient, and error-free method to (i) accurately locate and cut a sink basin opening and (ii) to mount a sink basin into a countertop.